Electric switch



2 Sheets-Sheet l ATTORNEY ad 1w 2 M w 14 w 5 6 0 /6 /6 2\7 9 W4 5 i fi 7m 9 iL @22 w r W5 e o 3 w @Q 5b c Q J w 31%.

July 1, 1947.

Filed Sept. 13, 1945 July 1, 1947. s, s GRADY 2,423,099

ELECTRIC SWITCH I Filed Sept. 13, 1945 2 Sheets-Sheet 2 ATTORNEYPatented July 1, 1947 UNITED STATE 5 RAT-EN OFF [CE ELECTRIC SWITCH-Stephen- S. Grady, New 21011:, N: iYI:

Application September 13,. 1'945,.Serial No;.61'6,073 I:

(Cll 200 -46-Y l '15 Claims. 1;

This inventionrelates to electric switches in general and more.especially to two-way switches, either for.alternatelyconnecting acommon generatorto one. or another of two power lines, or foralternately connecting a single power line to one or .ailotherof twogenerators.

Among. theobjects of the present invention, it is aimed toprovideaniirnproved two-way electric switch having a common fuse whenthe switch is either of its two closed positions and a slidableinterposer actuatable either into neutral position or into either of.the two closed positions ofthe switch.

It is still another objectof the presentinvention to provide an improvedelectric switch having a pivoted handle for actuating an interposer intoandout of closed position and a switch'box having 'acover cooperatingwith the handle so that thebox or cover. of the box cannot be openedwithout first actuating the switch handle into neutral or open position,and in turn whereby the opening of the cover will force the handle intoneutral or open position if it is not already in neutral position.

t is still another object of the present invention to providean improvedelectric switch having a pivoted handle for'actuating an interposer intoand out of oneoi two closed positions and a switch box havinga covercooperating with thehandle so that the 'box .or cover of the box cannotbe opened without first. actuating the switch handle into neutral oropen position, and in turn whereby the opening of the cover will forcethe handle .into neutral or open position whether the handle is inuoneor the other of its closed positions, if the handle is not already inneutral position.

It is still .another object of the present invention to provide animproved electric switch hava pivoted handle for actuating an interposerinto and out of closed position, and a switch-box having a cover andanchoring means locking said handle in neutral position when said coveris being removed or is removed and the cover will cooperate with saidanchoring means to free said handle when .said cover is actuated intoclosed position.

It is still another object of the present invention to provide animproved electric switch having .a pivoted handle for actuating aninterinto and out of closed position and a s chhox having. a cover, saidhandle consisting of two pieces pivoted to one anotherto enable foldingone piece into compact arrangement with the switch unit when the coveris removed 211;- to' conserve space-when shipping the switch andalsotoaifordjaccess-to a centrally located iu'sew It is still another"object of the-present invention to provide an improved-electric switchhav- "ing a plurality of parallel fuses with blade-enrls to cooperatewith flexible cla'mping- *jaws; and a bar constituting a fuse puller inanchoredpositl on securing gthe "several fuses from -"being accidently-jarred'loose; saidbar having a pin formed "to; enter any one' of' the-*-jaws when the bar'- ireed tocooperate with a *b'la'de end andremcve afuse;

These and otherfeature-s; capabilities and advantages of "the-presentinvention will *appear "from: the *subjoined 1 detail description of"'one specificembodiment"thereoi'* i1lustrated-- in the accompanyingdrawings in which Fig. '1 is I a side elevation -pai'tly in section" ofa switch heir and -electric 'switch- 'ma de' -accordin to the--'present' invention Fig-:12 is a plan view o? the electric "switchslightly enlarged as to 'tliescale of Figs-1;

actuate electric switohes of two; three and even fourassociated--=conduotors-;- as "fo'rinstancea two-wire direct currentcircuit, -a three-wire hookup: for a three-phase alternatirig --currenthookup or a four-wire hookup for a four-phase alternating currenthookups The-features of the present invention areadapte'd-to any one ofthese hookups;-an=d--merely by. way-of examplepin Fig.

2," there is illustrated an 'electric' -=switch *construction adaptedior i thi ee "electric SWitOl'lGs of three-associated conductors wo' witthe 'electric switches l, 2 and 3.

Since each of the electric switches l, 2 and 3 "is I substantiallyidentical with one another,- only oneswitch, to' wit theswltch 2 willb'de'scribed inrletail, and -the like parts in ele'ctricswitches l and 3will have-the same reference characters applied.

As shown-in Figs. 2 and-4gthere=is provided a.

base 4 composed of" some suitable insulating material common to allthree. switches I52 and 3,

and it is provided with "projections 5, 5 secured to thebase-wal1 6 ofthe -switch' "b0x .1 which in "turn-is provided with end-walls '8 andifithemall 8 having pivotally connected thereto, by the hinge I9, thecover II, which is provided with an overlapping or extended portion I2having an opening to receive the hasp I3 riveted to the flange I4 of thewa11 9. When the cover II is in closed position shown in Fig. 1, wherethe hasp I3 extends through the extension I2, a conventional padlock I5may be secured to the hasp I3 to lock the cover II in closed position.

When three switches, as an instance, the switches I, 2 and 3, areassociated, they are spaced from one another by the longitudinallyextending bars I6 and I1 composed of insulating material, with the barI6 between the switches I and 2 and the bar I1 between the switches 2and 3.

Extending transversely across the bars I6 and I1, there are provided thetwo plates I8 and I9 composed of insulating material, separated from oneanother and mounted on blocks or enlargements 23 composed of insulatingmaterial extending from the bars I6 and I1. Mounted on the transverseplates I8 and I9, there are provided the cheek plates 2I and 22 composedof insulating material and in alinement with the bars I6 and I1respectively to form stalls or working spaces for the switches I, 2 and3.

With particular reference to Figs. 2 and 4, each of the switches I, 2and 3 is provided with a main contact plate 23 secured to the base plate4 and provided with a terminal 24. This contact plate 23 extends fromone end of the base plate 4 ap-. proximately two-thirds the length ofthe base plate 4 and has a raised portion 25 with two cam faces .26 and21 at the ends of the raised portion 25. This raised portion is disposedin the present instance about midway between the transverse plates I8and I9. The transverse plates I8 and I9 have mounted on the same theU-shaped contact plates 28 and 29. Thelegs 39 and 3I of the contactplates 28 and 29 respectively are sub- 33 are secured to the plates 36and 31 respectively secured to the faces of the bars I9 and I8 extendingaway from the legs 30 and 3|. Between the plates 3'6, 31 and the barsI9, I8, preferably there are secured the webs 38 and 39 of the fuseclamping jaws 49 and 4| respectively.

The plates 36 and 31 have the flexible contact portions 42 and 43respectively extending toward one another in the space between theplates 32 and 33, the plates 36 and 31 having inclined shoulders 44 and45 respectively for the purposes hereinafter to be described.

The U-shaped contact plate 28 is insulated from J the edges of theplates 32 and 36 by the sheet 46 composed ofsome suitable insulatingmaterial and preferably extending up inside of the U- shaped plate28around the free edge of the plate 32, one portion of the bar I9 and thenupwardly between the opposing edges of the plate 28 and -plate.36.Similarly, the U-shaped plate 28 is insulated from the plate 33 and theplate 31 by the sheet 41 composed of a suitable insulating Ematerialwhich is disposed on the inside of the plate 35 and between the upperedge of the plate 35 and the plate 29 and then up over a portion i ofthe bar I8 to extend between the opposing edges of the plate 29 and theplate 31.

Mounted to slide on the bars I6 and I1 is the plate 48 composed ofinsulating material and having around its edges the U-shaped contactplates 49 and 50.

The plate 43 in the present instance is common to the three switches I,2 and 3 but each of the switches has an individual pair of contactplates 29 and 53.

For operating the plate 48 and its three sets of contact elements 49 and50 commonly known as an interposer, there are provided the two-arms 5iand 52. The bars 5I and 52 are pivotally connected by the pins 53 and 54to the upper ends of the cheek plates 2I and 22' and the lower ends ofthe bars 5i and 52 are enlarged, see Fig. 4, and have three fingers, 55,56 and 51 cooperating in three openings formed in the plate 48. The arms5I and 52 are operatively connected to two springs 58 and 59. Thesesprings are substantially identical to one another and cooperate withthe arms 5i and 52 to anchor the arms in neutral position againstaccidental displacement and also to anchor the arms in either of its twocircuit closing positions and still furthermore cooperate with the armsto effect a quick opening and quick closing in order to reduce arcing toa minimum.

The spring as an instance has one arm 60 disposed against the screw 6|constituting an abutment secured to the cheek plate 2!. This arm makes asingle turn around the screw 62 secured to the cheek plate 2! and thenpasses over to and under the projection 63 on the arm 5i and terminatesbeyond the projection 63 in the free arm element 64. The wire 58 isbentat 55 to form a seat for the projection 53 when the arm 5! is in neutralor open position of the switch. The portion 66 of the wire cooperateswith the abutment 63 to lock the arm 5| in one closed position, and thearm portion 64 cooperates with the abutment 63 to anchor the arm 5! inits other closed position.

The wire 59 of the arm 52 is similar to the wire 59 except that it isnot in alinement with the arm 53 but to a certain extent is thecomplement oi the wire 58, the wire 59 having an arm portion 51 abuttingagainst a screw similar to the screw 55 and. then making a complete turnaround another screw similar to the screw 62 and then extending downalong the cheek plate 22 and engaging the abutments 63 in the arm 52,the abutment 53 being similar to the abutmerit on the arm 5!. The wire59 also has a depression forming a seat cooperating with the abutment98. It will be noted, however, that in the present instance, the arm 60of the wire 58 extends adjacent to one end of the cheek plates 2i and 22while the similar free arm of the wire 59, see Fig. 2, extends adjacentthe other end of the switch. By this arrangement of the springs, thetension on the arms 5I and 52 to maintain them in either closed positionwill be substantially equal. 4

In order to actuate the two arms SI and 52 by a common lever, the leverhandle 69 is provided mounted on the blade 19 which is pivotallyconnected at one end to the arm 52 and slidably connected in a recess inthe arm 5i. When the handle 89 and blade 15 are positioned in the fullline position shown in Fig. 3, the handle 69 is ready to actuate thearms 5i and 52 into either of its closed positions or into neutralposition. When it is desired to ship the switch, however, in order toconserve space, the handle 69 is swung edge of the cheek plate 2|.

down into the dash and dotlline position show in Fig. 3ad-jacentthecheek plate 22..

In the present instance, the arm is provided with an extension having afinger .72 to rest-inthe-recess I3'formed in thespring plate-l4 which issecured-by the spring I5 to the upper The spring plate "l4 when itsrecess receivesthe pin i2 yieldably maintains-thearms 5| and52 inneutral position. The spring plate 14: has a pro'ection it which,seeFig-l, will be'engaged-by the cover ll to depress the spring-plate l4and thereby free the finger 1:2 from-the recess 13.

As will be herein-after described, the cov r 5 cooperates with thehandle 69 -tobring it into neutral position before thecover H can be re1noved.- When it returns the arm or handle B l 'intoneutra-l position,then the linger will register with the recess l3 and consequentlyimmediately that the cover II is raised, the spring plate I l will flexoutwardly and receive the finger-l2 andanchor the arms 5| and and the"handle B9=inneutral position. When it desired-to release the handle-69, it will be necessary to hex the spring plate 14 toward the cheekplate 2!. I This flexing can beachieved by merely closingthe cover lintothe position shown in Fig. 1.-

The handlefifi, see Fig. 1, has an enlargement 16 with a cam face Titocooperate with the edge "I8" ofthe-slot-IS in the cover Ii. The rearedge 99 of the handle 69 will in turn cooperate with the edge 8| of theopening 19. In other words, whenthe cover H is in closed position, themain die 69 extends through the opening is. The

opening 19 is so conformed that the handle Gil can -'be moved intoeither of its circuit closing positions, when the cover H is closed, butwhen the cover H is swung around its hinge it into open'position, if thehandle 69 is in either of its closed. positions, then either the edge l8of the opening 19 will cooperate with the cam face ll of the handlett orthe edge 8! of the opening '19 will cooperate with the edge-B8 of thehandle lifiinitially to return the handle 69 to its neutral position asshown in Fig. 1, when the finger I2 will register with the recess 13ready to be anchored bythe-spring plate 14 immediately that the cover Hclears the extension I5.

Inbperation the handle 59 from neutral position'may'actuate the arms 5|and 52 in turn to actuate the interposer 48 either to bring the contact'49 into engagement with the contact portions 34 and 3D and the contact53 on the plate 48 into engagement with the contacts 3! and 25 or elseswing the interposer48 into the other circuit closing position where thecontact will engage the contacts 35 and 3| and the contact as on :theplate 48' will engage the contact plates 42 and 25. Looking at Figs. 5and 6, assume that the binding posts'24 of the three switches l, 2 and 3are connected to the three conductors oi a generator; then when thehandle 69 is swung from neutral into closed position where theinterposer 48 causes, see Fig, 5, the contact 49 to engage theplates 32and 30 and causes the contact 59 to engage the contact plates 31 andthen the current will pass from a binding post 2d through the contactplate 25 to the contact 553, then the contact plate 31, then the clip 4!of the fuse, then the fuse 82 and then the fuse clip and from the fuseclip 40 to-thecontact plat the-contact 49 on the-interposer 48'and thenthe contact plate 3|l-to the-binding post or terminal 83 of the powerline connected to the contact sired to remove a fuse 92, the .bar

plate 30. .Inturn, see Fig. .6, whereitxis still assumed that thebinding posts 24' are connected to the conductor of a generator and .theinterposer 43 is swung into the otherclosed position of the switch, thecurrent .will pass from the binding post 24 through the contact plate25, then the contact 49 on the interposer '48, then the contact plate tothe clip 4t and through the fuse 82 to the clip 4|, and from the clip 4|to the contact plate 31, then the contact plate 33 to the contact on theinterposer 48, then to the contact plate 29' to the binding post orterminal 84 of the second power line.

Figs. 7 and 8, it is assumed that there are two generators or twogenerator systems connected to a single power line. lnFig. 7 it isassnrned that the conductor '85 connected to one generator is connectedto the binding post or terminal 83, the conductor 85 of another1gcnerator is connected to the binding post or terminal 84 and theconductor B! of the power line is connected to the terminal or bindingposti l. if the handle .59 is moved into the closing position of theswitch shown in Fig. 7, then the contact 355 of th interposer 43 willengage the contact plate 39 and the contact plate 32 and the com tact 59of theinterposer will engage the contact plates 25 and 31. Consequently,the generator connected to the conductor 85 will be brought intoconnection with the power line 8? and the current will pass from theconductor 85 through the contact plate 39 to the contact plate :49 onthe interposer 48, then the contact plate 32,..then the contact plate 39to the clip 40,.frorn theclip to through the fuse 82, to the clip 4| andfrom the clip ll to the contact plate 3; tothe contact in engagementwith th contact plate and from the contact plate 25 out to the bindingpost it to the power line 81.

In turn if the interposer 423 is swung into t e position shown in Fig.8, the generator I nected to the conductor E35 will be thrown connectionwith the power line 87 and the current will pass from the conductor Bilthrough the contact plate to the contact 59, from the contact 59 to thecontact plate 33 to the contact plate 3?, to the clip 45, from the clip4i thro the fuse 82, from the fuse 82 through the clip to the contactplate 35, from the contact plate to the contact 49 and then to thecontactiplate to the binding post 2=i in turn to the power line 83',

The several fuses 32 are ofconventional construction, each having attheir ends knife blades 83 and 89, the blade 83 being adapted to beclamped by a clip iii and the blade :89 to be clamped by a clip 4|.

When the switch as illustrated consists three switch elements, theseveral in niay be lockedin position by the bar 99, it b the presentinstance screw-threadedly cm W t to the upper edges of the cheek plates2i and at by the screws 9| and 92 respectively. in the present instanceis preferably with a pin 2 3 so that the bar 9E3 with its 1." may servea second function. In other words, when the bar99 is in the positionshown in Fig, 2, it will anchor the fuses 32 from being a withdrawn. Onthe other hand, i

- 7- .1 removed and then its pin may be u d to ssed into the space 94,see 3, N- ath the blade 88 or 85 of afuse 82 and then the pin 523 becaused to press against the blade 19% crate and withdraw upwardly a fus-82.

Furthermore, access is had to the fuse 82 located between the cheekplates 2| and 22 when the handle 69 is swung from the full line positionshown in Fig. 3 to the dash and dot line po sition shown in that figure.

It is obvious of course that in place of the fuse 82 of each unit whereit may be desired to dispense with a fuse, any suitable conductor suchas a copper bar may be substituted, in which case of course theadvantages of compactness afforded by the switch here disclosed willstill be retained, and the incidental features that flow from suchcompact arrangement as herein before discussed will also b retained.

It is obvious that various changes may be made to the details ofconstruction without departing from the general spirit of the inventionas set forth in the appended claims.

I claim:

1. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, and means for alternately connecting said mainterminal with either of said secondary terminals, said connecting meansincluding a common fuse, a fuse contact plate connected to each end offuse, a main contact plate connected to said main terminal, a secondarycontact plate connected to each of said secondary terminals, and an interposer slid'ably mounted between said main contact plate and thecontact plates of said fuse and of said secondary terminals, saidinterposer having two contacts and three main positions, an intermediateneutral position where its two contacts are free, one closed positionwhere one of its contacts bridges the gap between one fuse contact plateand the contact plate of one of said sec ondary terminals, and where theother of its contacts bridges the gap between the other fuse contactplate and the main contact plate, and the other closed position wheresaid other of its contacts bridges the gap between the other of saidfuse contact plates and the contact plate of the other of said secondaryterminals, nd where in turn the said first-mentioned of its contactsbridges the gap between said first-mentioned of its fuse contact platesand said main contact plate.

2. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, and means for alternately connecting said mainterminal with either of said secondary terminals, said connecting meansincluding a common fuse and an interposer having two contacts, saidinterposer being slidable into three positions, a neutral position whereits two contacts are free, one

closed position where one of its contacts bridges a gap between one endof said fuse and said main terminal, and the other contact bridges a gapbetween the other end of said fuse and one of said secondary terminals,and the other closed position where one of the contacts of saidinterposer closes a gap between one end of said fuse and said mainterminal, and the other contact closes a gap between the other end ofsaid fuse and the other of said secondary terminals.

3. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, and means for alternately connecting said mainterminal with either of said secondary terminals, said connecting meansincluding a common fuse, an interposer having two contacts, and separatecontact plates connected to said main terminal, to said secondaryterminals and to said fuse, being spaced from one another to form gaps,said interposer being slidable into three positions, a

neutral position where its two contacts are free, one closed positionwhere its contacts close a gap between said main terminal and one end ofsaid fuse and another gap between the other end of said fuse and one endof said secondary terminals, and another closed position where thecontacts of said interposer close a gap between said main terminal andone end of said fuse and another gap between the other end of said fuseand said other secondary terminal.

4. In an electric switch, the combination of a plurality of switchunits, each unit having a main terminal, a pair of secondary terminals,and means for alternately connecting the main terminal of each unit witheither of the secondary terminals of each unit, said connecting meansincluding a fuse for each unit, separate connecting plates connected tosaid main terminal, to said secondary terminals and to said fuse of eachunit being spaced from one another to form gaps, a common slidablymounted interposer having a pair of contacts for each unit, saidinterposer being slidable into three main positions, a neutral positionwhere its contacts are free, one closed position where the contacts ofeach unit close a gap between the main terminal and one end of the fuseand another gap between the other end of a fuse and one of the secondaryterminals of each unit, and the other closed position where the contactsof each unit close a gap between the main terminal and one end of a fuseand another gap between the other end of a fuse and the other secondaryterminal of each unit.

5. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, means for alternately connecting said main terminalwith either of said secondary terminals, said connecting means includinga common fuse and an interposer having two contacts, said interposerbeing slidable into three positions, a neutral position where its twocontacts are free, one closed position where one of its contacts bridgesa gap between one end of said fuse and said main terminal and the othercontact bridges a gap between the other end of said fuse and one of saidsecondary terminals, and the other closed position where one of thecontacts of said interposer closes a gap between one end of said fuseand said main terminal and the other contact closes a gap between theother end of said fuse and the other of said secondary terminals, apivotally mounted arm, the free end of said arm being operativelyconnected to said interposer, and a handle operatively connected to theother end of said arm for actuating said arm and in turn saidinterposer.

6. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, means for alternately connecting said main terminalwith either of said secondary terminals, said connecting means includinga common fuse and an interposer having two contacts, said interposerbeing slidable into three positions, a neutral position where its twocontacts are free, one closed position where one of its contacts bridgesa gap between one end of said fuse and said main terminal and the othercontact bridges a gap between the other end of said fuse and one of saidsecondary terminals, and the other closed position where one of thecontacts of said interposer closes a gap between one end of said fuseand said main terminal and the other contact closes a gap between theother end of said fuse and the other of said secondary terminals, apivotally mounted arm, the free end of said arm being operativelyconnected to said interposer, a handle operatively connected to theother end of said arm for actuating said arm and in turn saidinterposer, and a spring for yieldably anchoring said arm in its neutraland closed positions.

7. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, means for alternately connecting said main ter--minal with either of said secondary terminals, said connecting meansincluding a common fuse and an interposer having two contacts, saidinterposer being slidable into three positions, a neutral position whereits two contacts are free, one closed position where one of its contactsbridges a gap between one end of fuse and said main terminal and theother contact bridges a gap between the other end of said fuse and oneof said secondary terminals, and the other closed position where one ofthe contacts of said interposer closes a gap between one end of saidfuse and said main terminal and the other contact closes a gap betweenthe other end of said fuse and the other of said secondary terminals, apivotally mounted arm having its free end operatively connected to saidinterposer, a handle pivotally connected to the other end of said arm inone position to actuate said arm and in turn said interposer and theother position to be rocked out of the way to conserve space.

8. In an electric switch, the combination of a plurality of switchunits, each switch unit having a main terminal, a pair of secondaryterminals, means for alternately connecting the main terminal of eachunit with either of the secondary terminals of each unit, saidconnecting means including a. fuse for each unit, connecting platesconnected to the main terminal. secondary terminals and fuse of eachunit and forming gaps, a common slidably mounted interposer having apair of contacts for each unit, said interposer being slidable intothree maic posit ons, a neutral position where its contacts are free,one closed position where the contacts of each unit close a gap betweenthe main terminal and one end of the fuse and another gap between theother end of a, fuse and one of the secondary terminals of each unit,and the other closed position where the contacts of each unit close agap between the main terminal and one end of a fuse and another gapbetween the other end of a fuse and the other secondary terminal of eachunit, pivotally mounted arms having their free ends operativelyconnected to said interposer, a handle operatively connected to theother end. of said arm for actuating said arm, and spring means foranchoring said arm and in turn said interposer in its neutral and closedpositions.

9. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, means for alternately connecting said main terminalwith either of said secondary terminals, said connecting means includinga common fuse and an interposer having two contacts, said interposerbeing slidable into three positions, a neutral position where its twocontacts are free, one closed position where one of its contacts bridgesa gap between one end of said fuse and said main terminal and the othercontact bridges a gap between the other end of said fuse one of saidsecondary terminals, and the other closed position where one of thecontacts of said interposer closes a gap between one end of said fuseand said main terminal and the other contact closes a gap between theother end of said fuse and theother of said secondary terminals, ahousing for said switch having a, pivotallymounted cover having a slottherein, a pivotally mounted arm having its free end operativelyconnected to said interposer, a handle operatively connected to said armfor actuating the same and extending through the slot in said cover whensaid cover is closed, said cover cooperating with said handle toposition it in neutral position before said cover can be swung into openposition.

10. In an electric switch, the combination of a main terminal, a pair ofsecondary terminals, means for alternately connecting said main terminalwith either of said secondary terminals, said connecting means includinga common fuse and an interpose having two contacts, said interposerbeing slidable into three positions, a neutral position where its twocontacts, are free, one closed position where one of its contactsbridges a gap between one end of said fuse and said main terminal andthe other contact bridges a gap between the other end of said fuse andon of said secondary terminals, and the other closed position wher oneof the contacts of said interposer closes a gap between one end of saidfuse and said main terminal and the other contact closes a gap betweenthe other end of said fuse andthe other of said secondary terminals, ahousing for said switch, a pivotally mounted cover on said housinghaving, a slot, 9, pivotally mounted arm having its free end operativelyconnected withsaidinterposer to actuate the same, a handle operativelyconnected to said arm and extending through the slot in said cover, anda spring actuating means for anchoring said handle in neutral, positionwhen said cover is raised, said cover cooperating with said anchoringmeans to release said handle when said cover is in closed position toenable said handle to actuate said interposer.

11.. In al'l-GIGCtliC switch, the combination of a base, three switchunits mounted on said base, each switch unit having a main terminal, apair of secondary terminals and means for each unit for alternatelyconnecting its main terminal with either of its secondary terminals, theconnecting means of each including a common fuse, and connecting platesforming gaps between the main terminal and said fuse and between thesecondary terminals and said fuse, and a common interposer having a pairof contacts for each unit, said interposer being slidably mounted intothree main positions, a neutral position where the contacts are free,one closed position wher the contacts of each unit close a gap betweenits main terminal and one end of its fuse and close another gap betweenthe other end of its fuse and one of its secondary terminals and anotherclosed position where the contacts of each unit close a gap between itsmain terminal and one end of its fuse and close another gap between theother end of its fuse and the other of its secondary terminals, saidconnecting plates including clips for the ends of said fuses, said fuseshaving blade ends connected to said clips, said fuses being mountedparallel to one another, and an anchoring bar secured in place acrossthe ends of said fuses to lock the same against accidental displacement.

12. In an electric switch, the combination of a base, three switch unitsmounted on said base, each switch unit having a. main terminal, a pairof secondary terminals, and means for each unit for alternatelyconnecting its main terminal with either of its secondary terminals, theconnecting means of each including a common fuse, connecting platesforming gaps between the main terminal and said fuse and between thesecondary terminals and said fuse, a common interposer having a pair ofcontacts for each unit, said interposer being slidably mounted intothree main positions, a neutral position where the contacts are free,one closed position where the contacts of each unit close a gap betweenthe main terminal and one end of its fuse and close another gap betweenthe other end of its fuse and one .of its secondary terminals, andanother closed position where the contacts of each unit close a gapbetween its main terminal and one end of its fuse and close another gapbetween the other end of its fuse and the other of its secondaryterminals, said connecting plates including clips for the ends of saidfuses, said fuses having blade ends connected to said clips, said fusesbeing mounted parallel to one another, an anchoring bar secured in placeacross the ends of said fuses to lock the same against accidental displacement, and a finger at the end of said anchoring bar for engagingthe knife blades of said fuses when said bar is liberated to withdrawsaid fuses from said clips.

13. In an electric switch, the combination of a base, two parallel cheekplates mounted on said base forming three unit areas, an electric switchunit mounted in each unit area and including a main terminal, a pair ofsecondary terminals, means for alternately connecting each main terminalwith either of its associated secondary terminals, the connecting meansof each unit ineluding a common fuse disposed in each unit area,connecting plates for each unit connected to the main terminal,secondary terminals and fuse, of each unit to form gaps, a commoninterposer having a pair of contacts for each switch unit, theinterposer being slidably mounted into three main positions, a neutralposition where its contacts are free, one closed position where thecontacts of each unit close a gap between a, main terminal and one endof a fuse and the other end of a fuse with one of its secondaryterminals, and the other closed position where the contacts of each unitclose the gap between a main terminal and one end of a fuse and theother end of a fuse and the other of its secondary terminals.

14. In an electric switch, the combination of a base, two parallel cheekplates mounted on said base forming three unit areas, an electric switchunit mounted in each unit area and including a main terminal, a pair ofsecondary terminals, means for alternately connecting each main terminalwith either of its associated secondary terminals, the connecting meansof each unit including a common fuse disposed in each unit area,separate connecting plates for each unit connected to the main terminal,to the secondary terminals and to the fuse of each unit spaced from oneanother to form gaps, a common interposer having a pair of contacts foreach switch unit, the interposer being slidably mounted into three mainpositions, a neutral position where its contacts are free, one closedposition where the contacts of each unit close a gap between a mainterminal and one end of a fuse and the other end of a fuse with one ofits secondary terminals, and the other closed position where thecontacts of each unit close the gap between a main terminal and one endof a fuse and the other end of a fuse and the other of its secondaryterminals.

15. In an electric switch, the combination of a base, two parallel cheekplates mounted on said base forming three unit areas, an electric switchunit mounted in each unit area and including a main terminal, a pair ofsecondary terminals, means for alternately connecting each main terminalwith either of its associated secondary terminals, the connecting meansof each unit including a conductor disposed in each unit area, separateconnecting plates for each unit connected to the main terminal, to thesecondary terminals and to the conductor of each unit spaced from oneanother to form gaps, a common interposer having a pair of contacts foreach switch unit, the interposer being slidably mounted into three mainpositions, a neutral position where its contacts are free, one closedposition where the contacts of each unit close a gap between a mainterminal and one end of its conductor and the other end of its conductorwith one of its secondary terminals, and the other closed position wherethe contacts of each unit close the gap between a main terminal and oneend of its conductor and the other end of its conductor and the'other ofits secondary terminals.

STEPHEN S. GRADY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,905,001 Sachs Apr. 25, 19331,839,259 Meuer Nov. 29,1932 2,209,918 Hammerly July 30,1940

